Replacement parts for Carson STN-L3 trailer...

[WhiteWolf McBride]

Hokay guys...

Any of you Carson STN-L3 owners know that the plastic u-bolts for attaching the axles to the suspension arms are crap, right? Well, silly woofie went to go replace 'em with 2-56, 4-40 or 2.5mm threaded rod...

... and silly woofie let the wee rectangular saddle-pieces that the u-bolts go thru fall out of his pocket. Now he has to try to replace the 'saddles'. I've e-mail'd Carson Germany, Tamiya Canada, and even PMD.

Has anyone duplicated these pieces in metal, or know of substitutes Woofie could buy? I ~could~ use the pair I still have to make a mold and cast some in epoxy, but I'd rather have stronger ones that would hold up to a metal u-bolt. I'm thinking of using perforated metal sheet as used in microwave windows and such... but that's a sloppy make-do...

Anyone knowing of replacements, please et me know. I need the 12 rectangular pieces (mounted in pairs) & u-bolts (made out of 2.5mm rod w/ threaded ends if possible) and can supply the originals if someone is willing to make replacements for me. I can make the bolkts myself, would just have to source some rod, and a 2.5mm die (got 3mm and up already)

http://www.tamiyausa.com/pdf/manuals/907060ml.pdf (step #8)

WhiteWolf

[PaulNZ]

If you get stuck PM me, I think I can make those for you, just need the u bolt size and the axle dia. and also the size of the square section that they sit on, on the trailing arm.

[WhiteWolf McBride]

Thanks Paul...

I could send one of my pair of rectangular 'saddle' pieces so you could make 'em, then you'd have 'em if anyone else wants to replace 'em#

As for measurements: (referencing assembly sequence #8, seen in the afore-mentioned pdf file)

• the diameter of the axle where u-bolt sits in the depressions is 8.5mm;
• the width of the 'leaf' is 7.5mm;
• the diameter of the holes in the 'saddle' are 1.8mm;
• the unthreaded rod length between threaded u-bolt ends is 45mm;
• the thickness of the 'saddle' piece is 3mm, assumes I can acquire replacements, I'll need another 3mm of thread on each end;
• therefore full u-bolt rod length (unbent, before end-threading) would be: 45mm + (2x 3mm - saddles) + (2x 3mm - end-threads) = 57mm (6 pcs.)

I'm going to haul out my scrap perforated steel sheet to see if I can fab up a set of 'saddles', just for the **** of it. I'll see how difficult it is to make one set by hand (I need 6 pair, one for each leaf) using wire-cutters, metal files, and Dremel w/ carbide wheels & drill bits. One advantage to using the perf-sheet is with a piece on top of the leaf, another on the bottom of the axle, I can use regular bolts instead of u-bolts (though the u-bolts would still be better) I'll post pic's if I succeed...

I'll also let you all know how my inquiries to the various suppliers go... in case you want/need to do the same at some point.

WhiteWolf

PS: Anyone have a good mechanism for remote-activation of the ramps? I've seen various ones. This one uses a worm gear on the ramp hinge (yea, Bruder, but same idea!) I've also seen where the actuator is a servo-lever... Opinions? And ~NO~ hydraulics!

https://www.youtube.com/watch?v=ZCLcxScctV0

[ddc333]

You thought of these not sure but I think they could work

http://www.cti-modellbau.de/CTI-Hubzylinder/

[WhiteWolf McBride]

Hmmm,

Electric linear actuators. Interesting idea, but two problems: speed of actuation, and throw. Speed is fixed unless you use one of the delay-boards, and throw is ~fixed~.

Firgelli makes similar ones, and they are L12-R unit is R/C PnP: http://store.firgelli.com/L12_R_Line...ol_p/l12-r.htm

Prices run $70 from Firgelli US, $100 at Robotshop.ca w/o Customs, plus 13% tax. Then in looking for Firgelli's site again, found their other Canadian distributor, Phidgits.com (more options? not really: all too big) Oh, and the CTI ones are all 12v, the German model standard. That blows that idea away, as I'd hoped to stay on 7.2v-8.4v. packs.

The Firgelli L12-R 210:1 moves at 5mm/s, 30mm shortest throw; that's 6 seconds to 'actuate' - a tad fast (but that could be adjusted with a board). Don't think I can use 30mm of throw though, but the Euro ones might be slow and short enough.

I need to see how much throw I actually need first, and ~then~ see if an actuator or servo (or two) will do the deed. I can have them paired/linked pushing both sides - double the torque. Then I can slow the beasts down with a delay-board.

I should also consider two other ways to have the ramps move slowly: a worm-gear drive, as shown on the Bruder in the link I posted above; then there is Peter Müllers' ramp-actuator 'kit' on his Faun SLT 50-2 Elefant trailer. It uses two motors to push the crank-arm, the worm-gear is mounted inside. I wonder if a similar one could be made to fit in the Goldhofer. I may have to play about with some styrene scrap and Tamiya toy gearboxes - they have cheap wormgears.

Hmm, if I can prototype one in styrene, someone could replicate it in metal and make some dinero selling it to Carson's customers...

http://www.sonderfahrzeug-modellbau....ges/rampe1.jpg

WhiteWolf

[WhiteWolf McBride]

I just saw the smaller PQ-12 units, 20mm throw (even has limit-switches!) at $65 - they might do the trick.

Then I thought, mount 'em vertically, and you have remote Trailer legs! Not cheap though, at $65 each... (the Tamiya kit is $114 MSRP, and includes the 5th wheel control)

WhiteWolf...

~ need sleep... ~